I've read a lot of history. In every culture, in any time, there have been weak individuals, and people exploiting them for power. This isn't specific to a certain culture or country, it takes different forms, but vicious people will always use the strength of their ruthlessness and any other advantage they may have to maneuver themselves into positions where they can exploit the weak. For money, for power, just for kicks, whatever. I'm not sure what kind of sheltered lives people have where they get surprised by videos like these. This shit goes on constantly, everywhere, and it's hidden, because the weak don't have voices, and if they do, the powerful can suppress them. Teachers bullying kids is far more common than people think.
That's why we need to do what this guy did. Don't turn your eyes away when someone weak is suffering. If you suspect something's wrong, look into it. If you find evidence, expose the heaps of filthy shit that take advantage of the weak and use whatever medium you have at your disposal to fight them.